This invention relates to a workpiece supporting arrangement, for example, in the so-called empty stage of a transfer (multistage) press for large objects. The transfer press is of the type which is equipped with a transporting device, such as gripper rails, for transporting the workpieces from stage to stage and with tools disposed on and supported by displaceable tables. The empty stage in the press structure is provided with supporting elements which serve as supports for the workpieces and are adapted to their shape.
In transfer presses for large objects, in which large workpieces are processed in a number of sequential stages, empty stages are provided between the structural columns of the press since at those locations a work stage cannot be accommodated. The empty stages must be designed in such a manner that the respective workpiece, as it dwells in an empty stage between two work stages, is given a satisfactory support corresponding to its contour. This, however, means that a different support must be provided in the empty stage practically with every change of tools. In the past, such a change-over has been effected manually and has required a considerable amount of labor input.
One solution to resolve the problem of the time consuming support replacement is disclosed in U.S. patent application to Hacker et al, Ser. No. 536,035 filed Sept. 26th, 1983, now U.S. Pat. No. 4,503,766. According to the solution described therein, a plurality of point-shaped and/or small-area supporting elements are provided as depositories (workpiece positioning or supporting arrangements) in the empty stage and these depositories may be height adjustable piston rods or threaded spindles or the like to adapt their workpiece supporting end faces to the shape of the underside of the respective workpiece. While by means of this solution one and the same supporting mechanism may be set to any workpiece contour, it is relatively complex and expensive, particularly if computer control is involved.